shipping interior stuff

I'm sure that there have been earlier threads on this, but I couldn't seem to find one (give me a break it's late...) How would I ship odd or large items like seats, or door panels, stuff like that. And has anyone done this, who did they use to send them, and about how much was it?

Straighten the seats out, wrap em, put em in a box big enough fill with packing foam, put on a stamp and send.